The present invention relates to an auditory sense training method and sound processing method for auditory sense training which realizes an effective training for the great improvement of auditory perception, which is an obstacle to a person grown in an environment having a different language practice from learning another language or music of a different language environment.
Further, the present invention relates to an auditory sense training method and sound processing method for auditory sense training which may be used in medical areas such as the treatment for hypacusia and tinnitus, or music treatment.
[Regarding Auditory Sense]
The auditory sense of a person does not have a structure common to everyone, but rather, the structure of the auditory sense could be characterized by the language the person is using in their daily life. In other words, the structure of a person's auditory sense is advanced so that it works conveniently when listening to the language they use in their daily life.
In this specification, the structure of an auditory sense refers to the structure including the recognition ability of a vowel or a consonant, or the recognition ability of the attenuation of a tone and the like.
It is very rare in the Japanese language to end a word or a sentence by a consonant including many high frequency components of above 200 Hz for example. Rather, it ends by attenuating a vowel including many low frequency components.
Further, according to studies, it is now known that the Japanese especially sensitively percepts a vowel in a voice, and as a very special phenomenon, the Japanese are very sensitive to the reverberation included in a vowel (reverberation is likely to remain when the frequency is low).
These characteristics on the frequency band of the Japanese language and the sensitiveness of the Japanese native to the reverbaration sound or the attenuation sound show that the Japanese have a tendency to concentrate on the sound in the ending of a word.
That is, to a Japanese user, a peculiar or unique auditory sense structure which is appropriate for listening to and speaking Japanese is formed. Therefore, a voice which falls out of the peculiar auditory sense structure, for example, with a frequency component of above 2000 Hz, could not be recognized easily, and there is a tendency that the language having different pronunciation forms or grammar structure is hard to recognize.
Moreover, aging is another cause which makes it difficult for a person to recognize voice having high frequency regions.
On the other hand, in European languages such as English, German and Latin, high frequency components of over 2000 Hz are largely included, and some components even reach up to 6000 Hz.
That is, the language characteristics of an European language is opposite to Japanese in that the vowels only hold a dependent meaning, and that the recognition of the energy, the rising condition and the depth included in a consonant or the way to cut the consonant in the ending of a word is most important in recognizing the language. Moreover, the intonation, the strength, the accent and the like related to the grammar is important in recognizing the language. This could also be recognized from the fact that the native European language speakers are able to recognize the conversation of their language even by listening to voices whose frequency components of under 2000 Hz are reduced.
From the above mentioned fact, it could be seen that the Japanese have a tendency to recognize a vowel which does not exist, but on the other hand, may not recognize an existing consonant.
For example, the Japanese are known to have a low ability to recognize the rising of a consonant or to tell the high frequency components in a sound. One known example is that the Japanese have a low ability to tell the difference between the consonant of “L” and “R” or “M” and “N” in English.
Further, they recognize the word “McDonald” as “makudonarudo”, and “Seven Eleven” as “sebun irebun”, and pronounce such words by adding vowels.
That is, the above-mentioned words pronounced by the Japanese speaker is constituted according to the auditory sense structure of the Japanese language.
If the ability to recognize the rising of a consonant or to tell the high frequency components in a sound is low, the ability to pronounce the rising of a consonant or the high frequency components in a sound is also very low.
Therefore, according to the Japanese auditory sense structure mentioned above, it is difficult to either hear the language having a different language practice accurately or to pronounce such language as the native speakers.
In order to understand the structure of the auditory sense according to the Japanese language, the inventor performed an experiment where native Japanese speakers listened repeatedly to a voice processed to reduce its low frequency components and to strengthen a specific frequency band component, and came to the following conclusion.
Moreover, as a result of continuous experiment, a data was gained where the auditory sense would quickly switch back to the auditory structure as a Japanese native speaker when an unprocessed language is heard instead of the processed language.
Accordingly, it could be understood that in the auditory sense structure, the “recognition frequency” differs according to national, in other words, an “unrecognized frequency” exists according to national even if their tympanum may vibrate.
It is a problem yet to be solved in this unrecognized voice to find out what ability to recognize which frequency region is low and what training could there be to raise the ability to recognize those frequency region.
The characteristics of the language was mentioned above, but on the other hand, another unexpected fact was recognized by considering the characteristics regarding “conversation”.
The conversation involves not only listening to the meaning of the contents of the speaker's words, but the listener also tries to decide his or her correspondence by constantly anticipating the words of the speaker from its contents. This anticipation is not only performed based on the meaning of the words itself, but also by the listener listening to the language and feeling the delicate nuance of the attitude, the tone, the flow of breath, the expression on the face of the speaker and the like, and to decide based on the impression from the speaker. This anticipation involves the experience, the knowledge, the insight and the like of the listener.
Therefore, conversation is performed by responding to the speaker through anticipation of the conversation based on the feelings received from the speaker, other than the meaning that the words hold. Such element of the conversation other than the pure language is considered to even exceed 60% of the whole information.
As mentioned above, the ability to try and recognize in their mind the frequency component included in a voice which is unique to the language (which is called “perception frequency” in the specification) varies according to each national. Such difference of the recognizable frequency band between the national is not caused by the difference in the structure of the auditory organ, but by the difference in the consciousness of the listener.
Since the listener lacks large elements other than language in a conversation and lacks the auditory sense formed by the language practice when having a conversation in a foreign language, there may be caused a difference in the understanding of the speaker and the listener caused by the difference of the language environment or the culture, which may lead to misunderstanding or even a panic.
Therefore, in order to accurately listen to a foreign language and to acquire the language, there is a need to break the auditory sense structure constituted from the practice or the anticipation of one's mother tongue. Therefore, an effective means for learning language is to process by some method the sound itself of the language to learn.
[Regarding Music]
On the other hand, music, like scat and singing, could be recognized as an objective element of a language, and holds a characteristic as a developed state of a language, which means that music may comprise more subjective impressions or imaginations than the language itself. Therefore, in order to practice foreign music, such as western music, it is expected to be effective to break the auditory sense structure formed by the environment of different language practice, and to stop the thinking based on the Japanese language.
[Regarding Conventional Training Methods]
In the training of acquiring hearing skills for a foreign language, most of the prior art methods utilized media such as CD or a face-to-face method where the trainee listens repeatedly to the pronunciation of a native speaker in order to lean a native pronunciation.
Moreover, a method for improving the effect is further proposed where the hearing training is performed by using media comprising images which directly appeal to the sense of sight of the trainee.
Further, accompanied by the development of personal computers, there is also provided computer softwares which could be used like games where the trainee decides on a story, and hits the keys on the computer following the spelling displayed on the monitor in order to learn foreign words.
Moreover, there are methods of training where an English word which is difficult to hear is played back in slow-motion as disclosed in Japanese Patent Publication No. S60-159776, a device for emphasizing the pronunciation comprising a frequency that is hard to hear from the trainee as disclosed in Japanese Utility-Model Publication No. 30003950, a device for activating the brain by outputting English to either one of the left or right channels and outputting music to the other channel as disclosed in Japanese Patent Laid-Open Publication No. H2-196272, or a method for either repeatedly outputting a frequency-processed English or by mixing English into music as disclosed in Japanese Patent Laid-Open Publication No. H6-67596.
Moreover, a device for taking out the difficult-to-hear frequency region and to amplify that tone so as to compensate for the lack of auditory capacity in an auditory sense handicapped person is disclosed in Japanese Patent Laid-Open Publication No. S48-98698.
On the other hand, there were many methods from old times to learn a language with the rhythm of a percussion instrument or other music.
As a new technology, there is a unique method being invented where the foreign language is learned generally by image training accompanied by figures, music or the movement of the body.
In present years, most of the method for learning language is performed by listening to a language spoken by a native speaker or foreign lecturer, combining a method to improve the learning effect by various ideas.
However, those ideas which may seem unique does not fall out of the basic leaning method of repeating and experiencing.
For example, in the method where the trainee listens to music or synthetic sound or pulse which have been frequency-processed so as to simplify the listening of foreign language, the trainee merely gets used to the high frequency wave temporarily, which is the same as feeling an afterimage when seeing light in the dark. As a result of investigation, such result is not permanent, and not very effective as a training method.
It is true that high frequency is included in the western language such as English, but according to the studies by the inventor, the auditory sense is not so simple as recognizing a foreign language by merely listening and getting used to high frequency.
That is because listening to high frequency and recognizing a sound holds absolutely different problems.
Further, as for the amplifying device for compensating the lack of auditory capacity of an auditory sense handicapped person, it is performed against a patient who lacks normal auditory sense, and is a device for merely selectively compensating the lacked frequency band.
The difference between the prior art methods and the present invention will become apparent from the motivation and the object of the present invention disclosed hereinafter.
The above-mentioned prior art merely strengthens the frequency component included in the voice portion which is difficult to catch in learning a foreign language, and to temporarily improve the listening skill. Therefore, the auditory sense of the trainee will return to its normal status when the trainee listens to his or her mother tongue. Since the effect by such prior art method is not permanent, the training will need a long period of time for repeated training.
It is known that it is very effective in the learning of language to change the perception frequency. Therefore, it is necessary for the trainee to break off the anticipation and the like when speaking the mother tongue or the practice in everyday life.
The ability to catch a foreign language is not only a problem of different frequency, but there is also a need to consider the following points.    1) The problem of aging where the high frequency region becomes hard to catch by aging.    2) The actual frequency band that the Japanese feel difficulty in catching, and the training method for catching that high frequency is still not known.    3) Language should be understood by catching more generally the rhythm, flow, intonation, timing and language practice difference between languages.